kaizi, the sense is to build a secondary site with good content, exchange links with high PR directories and 301 the linkjuice to your primary site.
the problem with this solution is that google can definetely detect it, cause you're serving different content to customer & search engine ; ) visitors see the site, but the google crawler gets a 301 response.
now, if google crawls with a browser sig instead of the crawler signature, then they got it, and they do so as I know.
I guess they won't ban you, but possibly inflate the linkjuice.
my conclusion is I'd not waste to much time on such a bh project.